In pubs, bars and restaurants, carbonated beverages such as beer and soft drinks are generally dispensed from a cask or keg through a pipe to a dispense tap at the point of delivery. It is desirable for the beverage to be dispensed at a cool temperature. In the case of a highly carbonated beverage such as lager, it is particularly important that the beverage is cool because this prevents fobbing of the beverage when it is dispensed and efficient cooling of the beverage can therefore significantly reduce the time taken to dispense a measure of beverage.
conventionally therefore, the keg itself is cooled, for example by providing this in a cold environment such as a refrigerated cellar, so that the beverage delivered to the dispense tap is cool. Additionally or alternatively, an in-line cooler is provided to cool the beverage as it is supplied to the tap.
Where the keg is cooled, the beverage being dispensed through the tap must pass through a pipe between the keg and the dispense tap. As the pipe normally passes through a warm environment, the beverage will warm after leaving the keg. Especially where the dispense point is a long distance from the keg, or where the rate at which the beverage is dispensed is low, the beverage will remain in the pipe for a long period and therefore will be much warmer than the beverage in the keg. Therefore the beverage will not be at the desired temperature as it is dispensed and fobbing will occur on dispensing the beverage. Furthermore, the temperature of most cellars is controlled to the storage temperature for cask beverages. This temperature is greater than that at which it is desirable to dispense beverages from kegs, in particular lagers which are highly carbonated and more inclined to fobbing when dispensed if they are not sufficiently cooled.
Where a cooler is provided to cool the beverage as it is supplied to the dispense tap, to avoid the problem of cooled beverage warming as it remains in the pipe between the cooler and the dispense tap, the cooler is conventionally provided close to the dispense tap, and therefore takes up a lot of room near the bar and radiates heat into the bar area.
An alternative in-line system is the xe2x80x9cPythonxe2x80x9d system. In this system, the beverage is first passed through an in-line cooler such as an ice bath, and cold water is recirculated through a loop of pipe leading from the ice bath to the dispense point, the water being cooled at some point along the recirculating path. The beverage dispense pipes surround the loop of pipe carrying the cold water and the bundle of beverage pipes and water pipes is surrounded by an insulating jacket. Therefore the beverage is cooled by the cold water as the beverage is passed to the dispense point. Typically 8 to 12 beverage pipes surround two water pipes, one carrying the outward flow of water and the other carrying the return flow.
However, the Python system requires each beverage pipe to emerge from the Python bundle at some point to connect to a rap on the bar, and in the distance between the Python and the tap (typically about 2 meters) the beverage warms up, particularly if the beverage is not dispensed at a high rare and the beverage remains in the pipe for long periods of time. This causes considerable fobbing of the beverage on dispensing, which both increases the dispense time and causes wastage of beverage.
It has been suggested that to cool the beverage pipe between the Python and the tap, the flow of water through one of the Python lines could be directed through a coaxial pipe such that the cool water flows up the outer pipe surrounding the central pipe carrying the beverage. At the cap, the water would exit the coaxial pipe and flow back down to rejoin the Python. The coaxial pipe from the Python to the tap must have a diameter large enough to accommodate the beverage pipe, which typically has a xe2x85x9c inch diameter, plus the flow of water from the Python. The water pipe from the Python typically has a 15 mm diameter.
Many counter mounts do not have space to accommodate both a coaxial pipe of this size and the return water pipe which must be of the same size as the water pipe from the Python to accommodate the water flow. Reducing the cross sectional area of the coaxial pipe and accordingly reducing the diameter of the return water pipe will have the effect of throttling the flow of the Python and reducing its cooling effect. Replacing the counter mount with one having more space to accommodate larger pipes would be expensive and undesirable, as the particular shape and design of the counter mount is often distinctive to the brand of beverage.
According to the present invention, a cooled beverage supply system comprises:
a coaxial pipe having a central pipe for connection to a supply of beverage at a first end and for connection to a dispensing cap at a second end and an outer pipe for connection to a supply of cooled water at a first end and for connection to a return pipe at a second end adjacent the dispensing tap; and
a bypass pipe connecting the outer pipe to the return pipe and including a valve which may be opened to allow flow through the bypass pipe or closed to prevent flow through the bypass pipe.
The supply of cooled water and the supply of beverage are preferably from a beverage cooling system having at least one pipe carrying water and at least one pipe carrying beverage.
The central pipe of the coaxial pipe is typically connected to one of the beverage lines from the Python and the outer pipe is connected to one of the water lines. The cool water circulates up the outer pipe, keeping the beverage cool until it reaches the tap and returns to the Python via the return pipe. The bypass pipe is provided such that the size of the coaxial pipe and the return pipe may be reduced so that they fit inside any counter mount without throttling the flow of the Python. The combined capacity of the outer pipe and the bypass pipe should be at least equal to the capacity of the water line from the Python, and the flow of water from the Python is split between the bypass pipe and the flow to the tap through the outer pipe. The return pipe has the same flow capacity as the outer pipe.
However, the present inventors have found that when a bypass pipe is provided, when the system is started up the pressure of water is not sufficient to expel air from the water pipes to and from the tap. The narrower the water pipes to and from the dispense tap are, the more difficult it becomes to expel the air from the pipes, and an air lock is produced. Therefore, a valve is provided in the bypass pipe which is closed when the system is started up, so that the flow of water from the Python may only pass up the outer pipe of the coaxial pipe, providing sufficient pressure to expel air from the system. Once flow has started the valve may be opened and flow will continue by virtue of a syphon effect. At any point when an airlock occurs, this can be removed by closing the valve for a short period of time.
The present inventors have found that the use of the cooling system can reduce the dispense time for a pint of beverage from approximately 15-20 seconds, to 9 seconds because the fobbing of the beverage is considerably reduced.
The valve in the bypass pipe may be operated by a handle, but preferably it is operated by turning an implement such as a screwdriver or a coin in a slot. This prevents the valve from being closed accidentally when the system is operating. Preferably the valve is a ball valve.
Preferably, the beverage supply system includes a manifold having a first inlet for receiving a pipe containing beverage; a second inlet for connecting a pipe containing cooled water to a first chamber surrounding the beverage pipe; a first outlet for allowing the beverage pipe to exit the manifold coaxially with a surrounding water pipe which is in connection with the first chamber; a third inlet for connecting the return pipe to a second chamber; a second outlet in connection with the second chamber for connecting a pipe to allow water to exit the second chamber; a bypass pipe connecting the first and second chambers and having a valve which may be closed to prevent flow of water from the first chamber to the second chamber.